Use htmlSuite and htmlTest instead of ad hoc solution
Move test files into js and html sub directories
Merge pull request #126 from arv/html-tests

Html tests
Merge pull request #127 from arv/move-tests

Move tests
Make render invalidation smarter.

We only need to invalidate if:

- This is a shadow root
- This is a shadow host
- We are changing the select property
- We are a direct child of a shadow root (this is a bit too agressive)
- We are a direct child of a shadow host
Merge pull request #128 from arv/optimized-invalidate

Make render invalidation smarter.